Internet or web browsing has become one of the greatest uses of personal computing devices. Indeed web browsing has become such an integral part of everyday life that web browsers serve as the interface to many important and private tasks such as banking, shopping, bill-paying, securities purchases, investment/portfolio management, etc. To facilitate the general population's “wherever and whenever” desire for internet access, many public environments such as cafes, libraries, airport lounges, hotel business centers, etc., provide people with internet-connected public computers. These public computers often have high-speed internet connections using wireless communication links. They are also convenient to use since they normally have full-size keyboards and large displays. Accordingly, users of these public computers include not only people without a personal computing device, but also those who are carrying a mobile computing device limited by a smaller keyboard and/or display (e.g., laptop, personal data assistant, cellular phone with internet capabilities, etc.). In particular, display limitations of one's mobile computing device can make their use less than desirable for many web browsing tasks thereby making public computer use seem more attractive.
Unfortunately, public computers are usually far less trustworthy than one's own computer and mobile computing device. That is, public computers are far more likely to have malware or spyware operating thereon. Since public computers are used by many people to run different applications and visit various websites, it is very likely for them to be infected with malware or spyware. Such malware/spyware is designed to, for example, log user inputs to the computer (e.g., usernames and passwords), steal account information, and even secretly hijack a secure (e.g., HTTPS) web browsing session in order to facilitate fraudulent transactions. For these reasons, there are numerous articles and corporate warnings recommending that people not enter any “sensitive” information in a public computer. However, these warnings are often ignored since the “threats” are not visible to the user and, therefore, do not appear as ominous as they truly are.